Cylinder 1 Injector Circuit Low
The POWERSTROKE-P0261 (Power Stroke) diesel fault code means: Cylinder 1 Injector Circuit Low. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- advanced
- Estimated cost
- $400-$2,800 (single injector) up to $5,500 (full set of 8)
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View pilot availability →What Are the Symptoms of POWERSTROKE-P0261?
- Cylinder 1 misfire
- Rough idle
- Loss of power
- Smoke from exhaust
- CEL
What Causes POWERSTROKE-P0261? (Most Likely First)
- Failed cylinder 1 injector solenoid (6.0L injectors have a high failure rate) Very Likely
- Leaking oil rail o-rings (causes multiple cylinder codes) Likely
- Damaged harness under valve cover Likely
- Failed FICM driver channel Possible
Can I Still Drive with POWERSTROKE-P0261?
Short distances only. POWERSTROKE-P0261 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Common Fixes by Vehicle
What techs usually find when diagnosing POWERSTROKE-P0261 on specific platforms — tap a platform for the fix and the exact part:
2003-2007 Ford F-250/F-350 6.0L Power Stroke Advanced DIY
Injector cylinder 1 circuit low - on 6.0L this usually means the high-pressure oil rail is leaking at the STC (snap-to-connect) fitting or a stand pipe/dummy plug has cracked. Perform an air test on the high-pressure oil system; if it won't hold 30 psi, pull the valve covers and inspect stand pipes.
Labor: 4.0-6.0 hrsFrequently Asked Questions
What is P0261 on a 6.0L Power Stroke?
P0261 on a 6.0L Power Stroke (2003-2007) indicates: Cylinder 1 Injector Circuit Low. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.
Can I drive with P0261 on my Power Stroke?
Only drive short distances to get to a repair facility. Continued operation may cause further damage.
How much does it cost to fix P0261?
Repair cost is typically $400-$2,800 (single injector) up to $5,500 (full set of 8) depending on the underlying cause and whether you DIY or use a shop. Diagnostic time alone runs $100-$180 at most independent diesel shops.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose POWERSTROKE-P0261?
Perform KOER injector buzz test -- non-buzzing cylinder confirms bad injector or wiring to cylinder 1.
Check for high CCT (injector contribution) variance between cylinders.
If multiple cylinders report low-side issues, suspect leaking stand-pipes or oil rail o-rings.
Replace injector #1 as a set with at least the companion cylinder (pairs share oil rail).
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0261 as a generic OBD-II code)
P0261 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
Which Vehicles Commonly Get POWERSTROKE-P0261?
- 2003-2007 Ford F-250 Super Duty 6.0L Power Stroke
- 2003-2007 Ford F-350 Super Duty 6.0L Power Stroke
- 2003-2007 Ford F-450/F-550 Super Duty 6.0L Power Stroke
- 2003-2010 Ford E-350/E-450 6.0L Power Stroke
- 2003-2005 Ford Excursion 6.0L Power Stroke
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